CBD 101
THE BASICS ABOUT THE POPULAR HEALTH SUPPLEMENT EVERYONE IS TALKING ABOUT.
As you may have heard, there’s a new health supplement that’s vying for a spot in your medicine cabinet. Millions of people swear by it. Others, including many doctors, aren’t quite as sure, at least not yet. It’s CBD, which is shorthand for cannabidiol (pronounced canna-bi-dial), a natural, plant-based chemical compound that promises to reduce anxiety, pain, insomnia, and more. And suddenly, it’s everywhere.
The fact is, though much investigation into CBD is just beginning in the United States, it’s been around as part of folk remedies for thousands of years. Now, as a natural compound to soothe body and mind, CBD has captured the imagination of many in the health and wellness community. “CBD is anti-inflammatory, antibacterial, antianxiety, and immunosuppressive,” says Joseph Cohen, D.O., a Colorado physician. In fact, the National Academies of Sciences, Engineering, and Medicine convened a committee of experts to review cannabidiol’s effect for pain and insomnia. Their report suggested positive evidence that cannabidiol could be effective. Some experts see huge potential. “The brain is about a symphony,” neuroscientist Yasmin Hurd, Ph.D., told the New York Times, and she suspects CBD can “bring the entire symphony into harmony.”
The public reaction has been even more effusive, as CBD has made a bold entry into popular culture, media, and conversations nationwide. “Everyone who buys the product comes back and raves about it—including my mother,” a convenience-store clerk in North Carolina told the Washington Post. Elsewhere, one fan said, “Physically, it’s like taking a warm bath, melting the tension away.” When Prevention asked readers to share their CBD experiences, many responded with positive stories. “I use it twice a day,” one accountant wrote. “I also take it for pain and have been able to drastically reduce the amount of Advil and Aleve that I was taking on a daily basis.”
This book will provide just enough science and history to help you understand cannabidiol, but more important, it contains useful advice about considering, buying, and using CBD. Inside, you’ll find a condition-by-condition guide based on the most credible research available (starting on this page), an objective discussion of the hype around CBD (this page), as well as some of the limitations, unknowns, doubts, and serious questions to consider, along with insight on CBD’s intriguing potential (this page).
WHAT IS CBD?
CBD is one of more than 100 compounds known as cannabinoids, which are found in cannabis plants. Yes, CBD is from cannabis, but there are many different strains of the cannabis plant. Some strains are high in the chemical compound tetrahydrocannabinol (THC). Legally, in the United States, any cannabis strain with more than 0.3 percent THC is considered marijuana, famous for its psychoactive effects. There are other strains that contain high concentrations of CBD with little or no THC. Strains of cannabis with less than 0.3 percent of THC are known as hemp. CBD extracted from hemp plants does not have psychoactive effects, and it is this compound that’s found in the products available to you.
CBD doesn’t get you high, but according to proponents, it can bring relief to the body and mind in important ways, which is why it’s become a wellness phenomenon. In fact, these days, it’s more talked about than its well-known psychoactive sibling, THC. On Google, CBD passed THC in 2016 as the most widely searched cannabis compound. Today, it’s not even close. There are now more than three times as many searches for CBD every month. A 2019 Harris Poll found that 86 percent of US adults had heard of CBD and 18 percent had tried it—an impressive profile for a plant extract that was almost completely unknown just a few years ago.
The main reason for cannabidiol’s explosive growth? Early adopters—the people using CBD right now to help them with anxiety, insomnia, pain, or other conditions—often say that it’s effective. In a 2019 Prevention survey, more than two-thirds of CBD users said that it worked as they had hoped. In fact, 81 percent said they would be willing to spend $30 to $50 a month for cannabidiol. (Almost one in five said they’d pay at least $100 a month to keep their medicine cabinet stocked with CBD.) Overall, 78 percent said they’d recommend it.
This doesn’t mean the appeal is universal. In the Prevention survey, more than 20 percent said it didn’t work for them as they had hoped. But the experiences of the majority are creating a rare grassroots movement—a health-product boom that did not begin from big pharmaceutical companies. This compound, with its unique and fascinating history, is changing the landscape of how millions of Americans approach their health and wellness.
Of course, big business has noticed. When New York–based investment bank Cowen & Company studied the booming CBD market in 2018, they found that it was already between a $600 million and $2 billion business in the United States. (For comparison, the entire noncannabis herbal supplement market in 2017 was estimated at about $1 billion.) Even more striking: Cowen estimates that by 2025, the cannabidiol market will be $16 billion. The CBD research and analytics firm Brightfield Group is even more bullish, predicting that the CBD market will pass $23 billion by 2023, which would almost match the current revenue of Starbucks. “There is too much momentum…for this industry not to explode,” the group wrote. “Setting about sizing this market led us to speak with hundreds of people and crunch tens of thousands of numbers, leading us to understand that the hemp-derived CBD market is indeed growing at a breathtaking pace.”
My Take
I have pain in my lower back, shin splints in my left leg, and sciatica that affects my back and legs. I purchased a jar of CBD cream for $59. The salesperson said it would take about two weeks to be effective. I also purchased at the same time dark chocolate infused with CBD for about $22. They were somewhat effective together the first three days. But, when the chocolate ran out, not so much. I next bought a tincture. It was 500 milligrams for $49. It worked much better with the cream. I still could feel some pain, but at a lesser intensity. On my third week I bought an accelerant cream with 2,400 milligrams of CBD in the 2.5-ounce container. It was $79. It appears to help a little better. But the pain is still there. Overall, CBD is not as effective for me at the prices presently required for its purchase. —LaVerne Saunders, Chicago, Illinois
Where that growth will lead is hard to predict. But this is clear: CBD has captured the attention of the general public, and its popularity is soaring. There are countless companies selling CBD online, and it only takes a visit to a convenience store, health food store, drug store, supermarket, gas station—or that new CBD store that just popped up down the street—to find cannabidiol for sale near you, in a wide variety of forms. CBD can be purchased in oils, drops, creams, capsules, gummies, soaps, toothpicks, beard oil, breath sprays, lip balm, bath salts, pet products, and more. Seven percent of American adults use CBD, according to 2019 consumer surveys by both Harris and Cowen & Company. This translates to nearly 18 million US adults—and growing.
YOUR FIRST QUESTIONS ANSWERED
Cannabidiol’s newfound popularity raises some compelling questions, such as the following:
HOW COME I NEVER HEARD OF IT UNTIL RECENTLY?
Call it guilt by association. CBD isn’t truly new, but for almost 80 years it was largely hidden from the public because it comes from the cannabis plant. Until recent years, cannabis was illegal in all US states. Decades ago when authorities began cracking down on marijuana, the research and distribution of CBD in the United States stopped almost completely. (For more on the fascinating history of CBD, see Chapter 2.)
HOW DOES CBD WORK IN THE BODY?
Your body contains the endocannabinoid system, a network of receptors featuring key molecules known as cannabinoids. This network acts as a signaling system. When faced with a challenge, your body’s natural cannabinoids alert your system that hormones and other responses are needed to keep things in balance. For instance, if you overheat, this system alerts your body to sweat. You don’t store these internal cannabinoids in your body—you produce them only when they’re needed.
But here’s where it gets interesting. Remarkably, the cannabis plant produces cannabinoids as well. These were first discovered back in the 1940s, but were not as well understood until the 1990s. Scientists ultimately found that, when ingested, some of the plant’s cannabinoid compounds act similarly to the cannabinoids our bodies produce. One of the most compelling of these is cannabidiol, or CBD. According to CBD advocates, by ingesting CBD, you can complement your natural supply of cannabinoids and better arm your body to respond to challenges such as stress.
WHAT BENEFITS DOES IT BRING?
Because of the long ban on research in the United States, most of the studies on CBD are recent, short-term, and conducted on animals, not humans. But, to many observers, the research is encouraging. Studies involving rats and mice have shown that CBD has positive effects for pain, inflammation, and anxiety. And early research on humans shows promise for CBD as a sleep aid.
Meanwhile, anecdotal evidence is piling up, as millions of people try CBD and report their results to friends, doctors, and online. (Sprinkled throughout this book, you will find a sampling of these stories under the heading “My Take.”) Some people are disappointed and say the results are less than they expected, especially for the relatively high cost. (Prices vary, but a 30-count bottle of 25 milligram capsules often costs $60 or more.) But for others, it’s a small price to pay for what they say is true relief. Many report benefits for pain, anxiety, headache, insomnia, and other issues, including symptoms related to inflammation, menopause, and menstruation. Supporters often tout the advantage of taking a natural product with few if any side effects or risk of addiction, rather than relying on pharmaceutical medications, including opioids.
IS IT LEGAL?
Unlike marijuana, which is legal in some states, illegal in others, and still frowned upon by federal authorities, hemp—and the CBD that comes from it—is legal according to the US federal government. This is the result of the Farm Bill passed by Congress in 2018. In states that have legalized marijuana, it is legal to produce and sell CBD harvested from the marijuana plant. Elsewhere, CBD products come from hemp and are generally legal and available with no prescription required.
There are some exceptions. Two states—Nebraska and South Dakota—have yet to catch up with the federal law, and CBD products are still illegal there. In addition, Idaho follows stricter regulations than the federal law, effectively making many CBD products illegal there. In late 2019, the US Food and Drug Administration (FDA) released a statement declaring that it is illegal to market CBD as a food additive or dietary supplement, noting that it would continue to review the science and update its regulations as needed. (For more on CBD’s legal status, see this page.)
IS IT RISKY?
CBD is considered safe, though the FDA noted in 2019 that the safety data is based on limited science and unanswered questions remain. With all the new usage of cannabidiol, there have been some minor side effects reported (see this page), but for many people, there are no unexpected impacts at all. The good news so far: In most human studies involving CBD, only a tiny percentage of users have difficulty tolerating it. Cannabidiol is also known to be nonaddictive. Many doctors remain unsure whether CBD is effective or an example of the placebo effect—but even many skeptics in the medical community generally consider it rather harmless. Their main caution: The CBD that’s available in shops or online is currently subject to no government regulation, which means it may contain other ingredients or not even be CBD at all. It’s often advised that buyers research cannabidiol companies to make sure they are reputable, look for product lab reports and ingredient lists on websites, read reviews, and start with small doses. (For much more on buying smart, see Chapter 5.)
THE PROMISE OF CBD
Someday, science may have a full handle on exactly what CBD can and cannot do. But that day has yet to come. In the absence of long-term, double-blind, randomized, placebo-controlled human studies on cannabidiol’s effects, some proponents (with perhaps some wishful thinking) have created a long and inclusive list of potential powers for this little plant extract. The possibilities sometimes touted include help for acne, addiction, Alzheimer’s, anorexia, appetite reduction, beauty, cancer, depression, diabetes, digestive issues, glaucoma, heart disease, menstrual relief, migraines, multiple sclerosis, muscle spasms, nausea, nerve issues, Parkinson’s, post-traumatic stress disorder (PTSD), schizophrenia, sexual enhancement, skin care, weight loss, and more.
For some of these issues, no CBD-related relief may ever come. But for some others, researchers are already encouraged. One example is Esther Blessing, Ph.D., an assistant professor at New York University’s School of Medicine, whose research investigates CBD as a treatment for PTSD and alcohol use disorder. “CBD is the most promising drug that has come out for neuropsychiatric diseases in the last 50 years,” Blessing told the New York Times in 2018. “The reason it is so promising is that it has a unique combination of safety and effectiveness over a very broad range of conditions.”
Other research is showing that CBD may, at some point, play a role in quelling the deadly opioid epidemic. A 2015 study published in the journal Neurotherapeutics indicated that non-habit-forming CBD might help recovering opioid addicts avoid relapse, likely by reducing anxiety and cravings.
For most serious conditions, much more research is needed. As far back as 2012, a review of studies published in the British Journal of Clinical Pharmacology reported the far-from-definitive but nonetheless intriguing news that “evidence is emerging to suggest that CBD is a potent inhibitor of both cancer growth and spread.” Since then, research has not confirmed this early speculation, but more study is underway. A 2017 report from the National Academies of Sciences, Engineering, and Medicine found substantial evidence that cannabis (including both THC and CBD) is effective in treating muscle spasms and stiffness due to multiple sclerosis and helps with nausea and vomiting after chemotherapy. In an often-quoted Spanish study from 2010, an oral spray that included CBD was shown in a clinical trial to ward off those same chemotherapy effects.
Even when such hopeful signs emerge, medical experts caution that these are individual studies that, on their own, reveal only a small piece of the puzzle. More work is needed to understand CBD’s full value and limitations. (For a condition-by-condition listing, see Chapter 4.)
MOST POPULAR USES
While all kinds of future purposes for CBD may still be unrecognized or under early investigation, there are millions of people using it right now for anxiety, sleeplessness, inflammation, and pain. As CBD makes its splashy debut on the consciousness of health-minded people everywhere, it is being used for many conditions, but at its core, the public appeal so far centers on this tight circle of concerns. Most users don’t take it for general health and well-being, but rather to bring relief for a specific problem. In the 2019 Prevention CBD survey, people who had used CBD were asked to share their reasons (as many as they liked) and were given a variety of options to choose from. Of more than 800 total responses, 56 percent cited pain, while 48 percent said it was for anxiety; 32 percent included inflammation, and one in four chose insomnia. It’s a reality that plays out wherever CBD proponents gather. Online and in retail shops, the consistency is striking.
A 2019 Harris Poll found similar results. For this survey, while inflammation wasn’t offered as a choice, the other top responses struck a familiar chord. Fifty-five percent said they used CBD for relaxation, while 50 percent chose stress and anxiety relief. Forty-five percent cited sleep, while 44 percent said it was to treat muscle pain. (Other types of pains also scored high.) Scan the comment section for any online CBD product and you’ll note the same trend.
Stress and Sleep
It’s not surprising that a cannabis extract may be relaxing and sleep-inducing. After all, marijuana enthusiasts have been noticing the same effect for generations. In fact, part of that reaction has always been due to CBD, which is a natural compound in marijuana as well as in hemp. While CBD lacks the psychoactive power of THC, experts say it still can transform your mood. “CBD does change cognition,” says Jahan Marcu, Ph.D., COO, and director of experimental pharmacology and behavioral research at the International Research Center on Cannabis and Mental Health, in New York City. “CBD goes into the brain, where it affects receptors associated with mood, which is why people take it for anxiety.” With less anxiety often comes better sleep. Even a rare study from the 1980s showed that subjects who took 160 milligrams of CBD slept longer than those who took a placebo.
In 2018, Scott Shannon, M.D., assistant clinical professor at the University of Colorado, examined the records of 72 patients who used CBD for three months to help with anxiety and sleep. In the resulting study, which was published in the Permanente Journal, Dr. Shannon found “a fairly rapid decrease in anxiety scores that appears to persist for months.” In fact, anxiety scores decreased within the first month in 57 of the 72 patients and remained low. Dr. Shannon notes that at a time of great CBD hype, it is possible the placebo effect may have played a role, but he concludes that while more research is certainly needed, “cannabidiol may hold benefit for anxiety-related disorders.”
Research results do vary. In a double-blind human study at the University of Chicago, subjects were given CBD and then shown unpleasant images or words. The idea was to see if the calming effects of cannabidiol could help them handle the negative stimuli better than a control group. But, in this study, there was no difference in the emotional reaction of the CBD and placebo groups.
More intense: A 2012 study published in the journal Neuropsychopharmacology, in which Brazilian scientists pretreated mice with CBD and had them chased by a snake through a maze—clearly an anxiety-invoking situation. The CBD-fueled mice showed fewer panicked responses than those that received the placebo, and researchers concluded that they experienced less panic and fear. Even better news: All the mice survived this harrowing experience. And the point was made: Even in the toughest situations, at least according to this study, CBD can indeed be helpful with anxiety.
Pain and Inflammation
A majority of CBD users cited chronic pain and arthritis pain as their main reasons for trying CBD, according to a paper published in the journal Cannabis and Cannabinoid Research. It’s understandable. The CBD-pain connection has been long noted and remains persistent in the research. In a 2012 study using rodents, the National Institutes of Health found that “cannabinoids significantly suppress chronic inflammatory and neuropathic pain…(and) may represent a novel class of therapeutic agents for the treatment of chronic pain.” Since then, some other research has confirmed the optimism. A 2016 study using rodents published in the European Journal of Pain concluded that “topical CBD application has therapeutic potential for relief of arthritis pain-related behaviors and inflammation without evident side-effects.”
Some experts say that for CBD to be truly effective, it needs to be paired with THC, as it is in medical marijuana. There’s a fairly broad consensus for the effectiveness of medical marijuana as a pain reliever. That 2017 report from the National Academies of Sciences, Engineering, and Medicine said there was “conclusive or substantial evidence” that cannabis (including THC and CBD) is effective in treating chronic pain. A year later, Serbian scientists reviewed studies on medical cannabis (again, including both THC and CBD) and concluded that “the evidence from current research supports the use of medical cannabis in the treatment of chronic pain in adults.”
The question is how effective is CBD on its own. The full answer will require much further research, but proponents see reasons for optimism. For instance, a review of 132 original studies published in Frontiers in Neurology said that CBD can reduce inflammation in the body and help improve pain and mobility in patients with multiple sclerosis. “It is anti-inflammatory, antioxidative, antiemetic, antipsychotic and neuroprotective,” the review study authors wrote. Translation: As an antioxidant, CBD removes potentially damaging agents from the body. As an antiemetic, it is believed to be helpful in reducing nausea and vomiting. As an antipsychotic, it’s thought to be potentially effective against psychosis. As a neuroprotective, it may shield nerve cells from damage.
But it’s CBD’s promise as an anti-inflammatory that may be most exciting of all. If it can be proven to curb inflammation throughout the body, CBD would have enormous potential as a pain reliever and more. In a 2012 review, a researcher at the University of Mississippi found that CBD works as an anti-inflammatory in the tradition of popular drugstore over-the-counter pain medications (think Tylenol, Advil, Motrin). In fact, some observers have noted similarities between CBD and aspirin. For example, both come from a plant—in the case of aspirin, the active ingredient, salicylate, was first extracted from willow bark. Like CBD, aspirin had a long history as a popular natural healing remedy for centuries before taking its place in virtually every medicine cabinet in America.
For CBD, the potential may be even bigger than that—or not—but science will tell. A wide range of chronic disorders can be traced back to inflammation and oxidative stress (which is a potentially damaging imbalance between free radicals and antioxidants in your body). This can play a key role in conditions including schizophrenia, multiple sclerosis, rheumatoid arthritis, metabolic disorders, Alzheimer’s disease, Parkinson’s disease, diabetes, heart disease, short-term infections, and other ailments. The 2018 Serbian study noted that “inflammation and oxidative stress are intimately involved in the genesis of many human diseases,” concluding on a hopeful note that “the therapeutic utility of CBD is a relatively new area of investigation that portends new discoveries on the interplay between inflammation and oxidative stress, a relationship that underlies tissue and organ damage in many human diseases.”
When it comes to pain and inflammation, CBD’s biggest fans aren’t waiting for the scientists to catch up. They’re trying it and often reporting relief. What’s more, a large number are sharing the benefits with their friends—including their pets. Almost 40 percent of dog owners (and a third of cat owners) like the idea of CBD supplements for their pets, according to research by the marketing research firm Packaged Facts. There may be some reason for their optimism. A 2019 study at Cornell University College of Veterinary Medicine found that when dogs with arthritic joint pain were treated with CBD rather than a placebo, more than “80 percent of those taking CBD showed significant improvement in pain levels and quality of life,” without discernible side effects.
SEAL OF APPROVAL
While cannabidiol is being studied for all kinds of diseases and being used for familiar everyday concerns like relieving pain and sleeping better, it’s only been officially approved by the FDA for two particularly brutal childhood epilepsy syndromes known as Dravet syndrome and Lennox-Gastaut syndrome.
These conditions typically don’t respond to antiseizure medications. In multiple studies, extremely high doses of CBD reduced the number of seizures significantly and in some cases were able to stop the seizures altogether. In a field that normally sticks to the driest of language, the unbridled excitement of one 2017 Italian study is telling: “These are exciting times for research in cannabinoids,” wrote a researcher. “After almost four millennia of their documented medical use in the treatment of seizure disorders, we are very close to obtaining conclusive evidence of their efficacy in some severe epilepsy syndromes. The era of evidence-based prescription of a cannabis product is within our sight.” The researcher, Emilio Perucca, was right. In 2018, the FDA approved a drug called Epidiolex specifically for these severe conditions.
Unlike drugs that synthetically mimic parts of the cannabis plant, Epidiolex is all natural, coming completely from the cannabis plant and containing only CBD. It’s not yet certain exactly how Epidiolex works. It may inhibit or slow down the way signals are sent to the brain. Some researchers think Epidiolex adjusts how much calcium can get inside the nerves. When a nerve cell has too much calcium, it fires electric pulses too fast. These electrical overloads cause damage inside the cell during seizures. The CBD medication appears to maintain a healthy balance of calcium in those nerve cells. Like most medications, it doesn’t work for everyone, but clinical trials found that seizures decreased, on average by about half.
It worked even better than that for Billy Caldwell, an 11-year-old boy in Northern Ireland who in 2017 became the first person to receive a prescription for medical cannabis in the UK. He had been suffering as many as 100 seizures per day, according to his mother, Charlotte Caldwell. These seizures amounted to a beating on his brain that seemed destined to lead to his death. But that destiny changed when in the first 300 days after his CBD prescription, Billy suffered zero seizures. (By the summer of 2019, Northern Irish authorities had reversed course and blocked doctors from prescribing medical cannabis, forcing the Caldwells into a legal challenge to keep receiving the product legally.)
From the start, the story of CBD and epilepsy is the tale of parents fighting (and innovating) to save their children. Neuroscientist Catherine Jacobson, Ph.D., took up the battle when her own son was suffering seizures as a baby. Using her insights as a researcher, Jacobson became a central figure in CBD’s incredibly fast rise in the epilepsy community. As more parents of suffering children discovered the potential of CBD, the pressure mounted on officials to speed through trials, to make it more widely available, and to legalize it. In a field where drug development and approvals can be interminably long and tedious, parents helped CBD to go from obscurity to full FDA approval in a remarkable six years.
The story was so powerful it was featured in a memorable 2019 New York Times Magazine article, authored by Moises Velasquez-Manoff, who wrote: “Epidiolex is also noteworthy for its unusual history. Drugs are typically developed in the lab and go through trials before reaching patients. But in the case of Epidiolex, two mothers of epileptic children experimented on their own sons and then helped push a version of what they discovered into the FDA pipeline. ‘In the modern era, it’s certainly the most striking example of a drug that has gone from patient use to drug development,’ Ken Mackie, a neuroscientist at Indiana University, told me. And it’s unlikely to be the last such example. Because so many people already use cannabis and think it helps, patients might be, in effect, pioneering new uses through self-experimentation.”
In other words, medical science still doesn’t exactly know everything CBD can do. Some of those answers may ultimately be discovered by the people who are using CBD now. As the epilepsy story shows, CBD has developed as a kind of folk movement, popular among the people long before governments know enough to approve. And that trend continues today.
It’s no surprise that some of the medical community has taken its usual and understandable approach: caution. Perhaps the surprise is how quickly everyday people have come to love CBD. In the 2019 Prevention survey, 72 percent of users rated their experience with CBD as good or very good. Only 3 percent said it was bad or very bad. Other polls show similar results. In the 2018 survey in the journal Cannabis and Cannabinoid Research, large percentages reported success with CBD, with 35 percent giving it the highest grade. Only 4 percent said it didn’t work for them at all. In a 2019 Gallup poll of those familiar with CBD, 78 percent said it had at least some health benefits and a sizable portion (a third overall) said cannabidiol delivered a lot of health benefits. Only 4 percent said it didn’t have any. More than six in ten respondents favored its availability over the counter, while only 4 percent believed it shouldn’t be for sale at all—a surprising acceptance for an extract that comes from a plant as historically controversial as cannabis.
THE CONCERNS
CBD has gained popularity so fast that many people are suspicious—that it’s just a fad, that it’s an example of the placebo effect, that it’s not based on real science. Some worry that it’s not been vetted enough to be truly safe, or that—since it’s largely unregulated—it’s impossible to know what you’re getting when you buy it. These are legitimate concerns worth exploring.
One informed skeptic is Pal Pacher, M.D., Ph.D., an investigator at the National Institutes of Health and former president of the International Cannabinoid Research Society. After many years of studying the issue, Dr. Pacher says that there’s no real proof that CBD works as well as proponents say, except in the case of epilepsy. He stresses that more research is needed.
“There are numerous animal studies which show different benefits, but none of these were confirmed in clinical studies so far, and several were actually shown in clinical trials to fail,” Dr. Pacher says. “It is relatively safe, so I have no problem if people want to take it. And if they feel better, that’s fine. As far as we know, though, this may all be mostly a placebo effect. The placebo effect is very, very strong.”
As a respected researcher on the topic, Dr. Pacher set off alarm bells in the CBD world when he was quoted in Newsweek saying that the CBD phenomenon amounts to “one of the largest uncontrolled clinical trials in history, and no one really knows what it is they’re taking. Everybody is being sucked into the big hype.” He worries that, without solid, long-term research, CBD’s buzz is way ahead of the science. To some degree, the FDA agrees. “There are many unanswered questions about the science, safety, and quality of products containing CBD,” the FDA wrote in a 2019 consumer update.
Even the most ardent CBD proponents would concede a relative lack of rigorous human-based studies that are scientifically rock solid (meaning long-term, double-blind, and placebo-controlled), illustrating the benefits of cannabidiol in a virtually unassailable way. Those same proponents might also point out that there also hasn’t been a torrent of such research showing that CBD doesn’t work either. Both points are true. Some of the most talked-about research has come from observational studies, which follow patients’ improvement after taking CBD, without the scientific controls that would make the research more valid. The only exception is in the study of seizures. In the run-up to FDA approval for Epidiolex, promising human-based studies were completed, though there hasn’t been enough time yet for long-term research. For other uses, the formal study of CBD is still in its infancy.
Not all experts are as skeptical as Dr. Pacher, but all agree more study is needed. “The basic science and preclinical research is quite strong,” says Dr. Shannon, the Colorado psychiatrist who has studied the effects of CBD on sleep and anxiety. “We have a good understanding of why this is likely to be a useful medical intervention. But we have little good data in humans.”
ON DOUBT AND DOSAGE
Some studies that have gained positive attention for CBD are often much smaller than what is expected when investigating a new treatment or drug. A 2011 Brazilian study is often cited by CBD advocates for showing that cannabidiol lowered anxiety and discomfort for people involved in a public-speaking exercise. What got less attention: The study involved just two dozen people. Other studies are even smaller.
For some researchers, small or short-term studies are too flimsy for solid conclusions. The evidence is too scant for Frederico Garcia, M.D., Ph.D., a professor at Brazil’s Federal University of Minas Gerais. In 2017, he looked at the CBD-related research for psychiatric conditions for an article published in the World Journal of Biological Psychiatry and concluded that he couldn’t recommend it, despite the fact that many of his colleagues were excited by cannabidiol’s potential. “CBD is being touted as safe and effective for several psychiatric disorders, but the data available do not prove that. The results of our review demonstrate that the use of CBD for psychiatric disorders should be regarded with caution.” Such disagreements among medical experts are now common.
The fact is, trial and error doesn’t happen instantly, and progress isn’t always a straight line. Even some of the studies commonly cited by CBD supporters show uneven results. The Colorado anxiety report cited earlier in this chapter (this page), for instance, also looked at the effect of CBD on sleep. For anxiety, nearly 80 percent of CBD users saw improvement that persisted for the three-month study, a fact that garnered headlines and mentions in various media. For sleep, it was a different story. Two-thirds of patients did see improvement in their sleep in the first month, but those benefits soon faded. This fact got considerably less attention. Does it mean the brain builds up a tolerance? Perhaps time will tell. Meanwhile, other studies have found the exact opposite, with CBD providing impressive benefits for sleep but not anxiety.
Such mixed results are not unusual—for CBD or anything else. Even a proven pain reliever like Tylenol fails in some trials. And doctors often caution that no substance works for each person’s body in the same way. With CBD, some users report relief. Others feel nothing. With all the attention on cannabidiol, study results are interpreted and applied in real time, as they happen. In some cases, if the result isn’t stellar, it’s seen as a failure for CBD, when in fact, it may be exactly that, or maybe it was just the wrong dose.
Since much remains unknown about CBD, there are many questions about the right amount necessary for various uses. One piece of common dosing advice is to start with 10 milligrams and adjust upward. More aggressive guidance recommends taking 1 to 6 milligrams for every 10 pounds of body weight, then adjust within that wide range depending on results. But unlike most medications, no one knows the perfect dose.
The majority of medical professionals—especially the ones who work with patients every day—have virtually no training in the area of cannabidiol, which means they can’t help much on questions such as dosage. Their medical-school textbooks surely didn’t focus on obscure old folk remedies from the cannabis plant. (The good news: Professional seminars about CBD are suddenly popular as doctors scramble to understand how it works and what to advise.)
Dr. Pacher, the leading cannabidiol NIH researcher who has reviewed virtually every CBD study, notes that the rodents in the studies are almost always very small, yet the dose of CBD remains relatively large. “In most of the studies, CBD was effective for the rodents at around 10 milligrams per kilogram of body weight,” Dr. Pacher says. This translates to 10 milligrams for every 2.2 pounds. “This means in a person of 80 kilograms [about 175 pounds] you might need a single dose of 800 milligrams.”
Dr. Pacher’s point is that most people are getting a whole lot less than that. “When you buy a cannabidiol product, usually it contains 100 to 500 milligrams in a whole vial, which you might be taking for a month or something like that. It would mean the dose that you are consuming is ten- to one hundredfold less than any dose that has been proven in any animal or human trial.”
Researchers are currently experimenting with different amounts in their studies. In the long term, this will yield insights that will help users zero in on exactly how much CBD they need. These are measures that science works out through years of study. After all, there was a time when experts were still tweaking how many aspirin a patient might require for relief. It took time and research to figure it out. This is currently just beginning to happen for cannabidiol. But, of course, in the hyped CBD environment, many people are diving in and trying to figure it out for themselves.
In that Brazilian public-speaking study, subjects lowered their anxiety when treated with a megadose of 600 milligrams of CBD—that’s higher than an entire typical 500-milligram bottle of tincture and much more than almost all CBD users ever take at one time. A different 2017 study gave varying doses of CBD to 60 volunteers for a single public-speaking test. It found that those who took 300 milligrams showed lower anxiety than those who took 100 milligrams or 900 milligrams. What’s a potential CBD buyer to think? (For a general dosage recommendation, turn to this page.)
My Take
My experience with CBD oil is that it does relieve arthritic pain in large joints (hips, knees, shoulders), as well as the neck, wrists, and thumb joint. It is also effective for helping me to fall asleep at night. I take 25 milligrams twice a day: noon and bedtime. If I wake up in pain during the night, I take another dose (5 to 6 hours after the bedtime dose), which relieves the pain and helps me get back to sleep. It does cause “dry mouth,” but only when I take it during the night when I am in bed.
But all CBD oil isn’t created equal. Some brands are inferior to others. It’s best to buy a name brand that has a good reputation. Advil, Aleve, Ibuprofen did not work for me, which is probably good as long-term use of these products can cause intestinal bleeding and other problems. For me, CBD has no such side effects.
—C. W., Seattle, Washington
QUALITY CONTROL
While most experts consider CBD to be safe, and many are confident that further research will confirm some level of effectiveness, there remains a major concern when it comes to the CBD that you can purchase. In this new, unregulated field, it’s hard to be completely sure that what you buy is what you think it is. There’s no regulation, which means unscrupulous or sloppy manufacturers can bottle whatever they like under the name CBD.
“This market is largely buyer beware—with unlicensed manufacturers and sellers promoting a non-standardized product,” says Paul Armentano, deputy director of the National Organization for the Reform of Marijuana Laws (NORML). Terms like “snake oil,” “free-for-all,” and “wild West” often pop up when medical experts are discussing CBD, and the fact is that some CBD is mislabeled or contaminated or contains dangerous ingredients. When Virginia Commonwealth University researchers chemically analyzed nine CBD vaping liquids, they discovered that four of the nine contained the dangerous synthetic cannabinoid known as Spice, and one had the cough suppressant dextromethorphan. In a 2017 study in the Journal of the American Medical Association (JAMA), the amount of CBD for most of the products tested didn’t match the label. At the time, one of the study’s coauthors said “there’s a 75 percent chance of getting a product where the CBD is mislabeled.”
This isn’t just an American problem. When Britain’s Centre for Medicinal Cannabis bought CBD oil for testing, it found that more than half of the purchased products did not contain the level of CBD promised on the label. Dr. Pacher describes a report presented at a recent meeting of the International Cannabis Research Society. “The researchers got CBD from approved vendors. It was quite shocking,” he says. “In some of the products there was no CBD. In other products, there was CBD but it was heavily contaminated with THC. So, let’s say it’s effective. You will never know what is really causing the effect. How will you reproduce it? Maybe next time you will get something different. That’s the problem. You don’t really know what you’re taking.”
The worries have clearly filtered down to the buying public. In the 2019 Prevention survey, when respondents were asked about their biggest CBD concerns, the two most commonly chosen responses were “I can’t be sure of the quality” (46 percent) and “not sure if it’s safe” (28 percent).
State governments and the CBD industry recognize the problem and are stepping in to try to bring some standardization to the field. Colorado and Oregon have laws to ensure that CBD isn’t tainted by too much THC or by other contaminants. Indiana and Utah require CBD products that are sold at retail stores to include a QR code, which allows consumers to instantly check out the product’s “certificate of analysis” (COA), showing the testing the company did and the exact levels of CBD and THC. An industry group called the US Hemp Authority (ushempauthority.org) provides certified seals to companies that meet specific quality standards. (For a complete guide to buying CBD smartly and safely, see Chapter 5.)